Imaging technique for use with optical MEMS devices

Abstract

Using an imaging system, an optical MEMS devices is imaged so that in combination with an actual one or more other optical MEMS devices, or images thereof, a single virtual optical MEMS device is formed that has the size of each of the optical MEMS devices combined. The physical size of the arrangement may be reduced by compacting the optical path, e.g., using appropriate conventional mirrors, and/or employing folded arrangements, i.e., arrangements in which there is only one MEMS device stage that does double duty for both input and output through the use of at least one conventional mirror. The imaging system may reproduce the angle of reflection of the light from the micro mirror, e.g., using a telecentric system. A prism may be employed to align the various optical MEMS devices, or images thereof.

What is claimed is:  
     
       1. An optical switch, comprising 
       a first micro-electromechanical system (MEMS) device containing a first number of micro mirrors;  
       a second MEMS device containing a second number of micro mirrors; and  
       a first imaging system optically coupled to said first MEMS device at one optical end so as to produce an image of said first MEMS device at the optical end of said imaging system opposite to said optical end at which said first MEMS device is located;  
       wherein  
       (i) said image of said first MEMS device and  
       (ii) at least one of the set consisting of (a) said second MEMS device and (b) an image of said second MEMS device,  
       form a virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers.  
     
     
       2. The invention as defined in  claim 1  wherein said image of said first MEMS device is made up of light beams reflected by said micro mirrors of said first MEMS device, each of said light beams having an angle that is a function of the angle of reflection of said light beam from a respective one of said micro mirrors of said first MEMS device off of which it was reflected. 
     
     
       3. The invention as defined in  claim 1  wherein said first number and said second number are the same. 
     
     
       4. The invention as defined in  claim 1  wherein said image of said first MEMS device is made up of light beams reflected by said micro mirrors of said first MEMS device and said imaging system reproduces the angle of reflection of each beam of light from each respective one of said micro mirrors of said first MEMS device off of which it was reflected. 
     
     
       5. The invention as defined in  claim 1  wherein said imaging system is a telecentric system. 
     
     
       6. The invention as defined in  claim 1  further comprising a prism for bending light beams coming from the direction of, or going in the direction towards, said first imaging system. 
     
     
       7. The invention as defined in  claim 1  further comprising a mirror for bending light beams coming from the direction of, or going in the direction towards, said first MEMS device. 
     
     
       8. The invention as defined in  claim 1  further comprising: 
       a field lens system for processing light which appears to be coming from the direction of, or going in the direction towards, said virtual MEMS device.  
     
     
       9. The invention as defined in  claim 1  further comprising an optical fiber bundle containing at least one fiber for supplying light to at least one of the group consisting said first MEMS device and said second MEMS device. 
     
     
       10. The invention as defined in  claim 1  further comprising an optical fiber bundle containing at least one fiber for receiving light from at least one of the group consisting of said first MEMS device and said second MEMS device. 
     
     
       11. The invention as defined in  claim 1  further comprising a third MEMS device containing a third number of micro mirrors, said micro mirrors of said third MEMS device being arranged to reflect light which appears to be coming from said virtual MEMS device. 
     
     
       12. The invention as defined in  claim 1  further comprising a third MEMS device a containing third number of micro mirrors, said micro mirrors of said third MEMS device being arranged to reflect light onto various micro mirrors of said virtual MEMS device. 
     
     
       13. The invention as defined in  claim 1  further comprising a mirror arranged to reflect said image of said virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers back toward said image whereby a cross connect with a folded configuration is formed. 
     
     
       14. The invention as defined in  claim 1  wherein said first imaging system includes at least one mirror which is placed to achieve a compact configuration. 
     
     
       15. The invention as defined in  claim 1  wherein 
       a third micro-electromechanical system (MEMS) device containing a third number of micro mirrors;  
       a fourth MEMS device containing a fourth number of micro mirrors; and  
       a second imaging system optically coupled to said third MEMS device at optical one end so as to produce an image of said third MEMS device at the optical end of said imaging system opposite to said optical end at which said third MEMS device is located;  
       wherein said fourth imaging system is arranged so that (i) said image of said third MEMS device and (ii) at least one of the set consisting of said fourth MEMS device and an image of said fourth MEMS device, form a virtual MEMS device having a number of micro mirrors equal to the sum of said third and fourth numbers; and  
       wherein said virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers and said virtual MEMS device having a number of micro mirrors equal to the sum of said third and fourth numbers are arranged to form a cross-connect.  
     
     
       16. The invention as defined in  claim 15  wherein said third number and said fourth number are the same. 
     
     
       17. The invention as defined in  claim 15  wherein said first number, said second number, said third number and said fourth number are the same. 
     
     
       18. The invention as defined in  claim 15  wherein said second imaging system includes at least one mirror which is placed to achieve a compact configuration. 
     
     
       19. The invention as defined in  claim 15  further comprising at least one mirror, and wherein said virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers and said virtual MEMS device having a number of micro mirrors equal to the sum of said third and fourth numbers are arranged to be adjacent to each other so as to form a virtual MEMS device having a number of micro mirrors equal to the sum of said first, said second, said third and said fourth numbers, said mirror being placed so as to reflect said image of said virtual MEMS device having a number of micro mirrors equal to the sum of said first, said second, said third and said fourth numbers back toward said image of said virtual MEMS device having a number of micro mirrors equal to the sum of said first, said second, said third and said fourth numbers so as to form a cross connect with a folded configuration. 
     
     
       20. The invention as defined in  claim 1  further comprising: 
       a third micro-electromechanical system (MEMS) device containing a third number of micro mirrors;  
       a fourth MEMS device containing a fourth number of micro mirrors; and  
       a second imaging system optically coupled to said third MEMS device at one optical end so as to produce an image of said third MEMS device at the optical end of said imaging system opposite to said optical end at which said third MEMS device is located;  
       wherein said fourth imaging system is arranged so that (i) said image of said third MEMS device and (ii) at least one of the set consisting of said fourth MEMS device and an image of said fourth MEMS device, form a virtual MEMS device having a number of micro mirrors equal to the sum of said third and fourth numbers;  
       and wherein said virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers and said image of a virtual MEMS device having a number of micro mirrors equal to the sum of said third and fourth numbers are arranged to be adjacent to each other so as to form a virtual MEMS device having a number of micro mirrors equal to the sum of said first, said second, said third and said fourth numbers.  
     
     
       21. The invention as defined in  claim 20  wherein said virtual MEMS device having a number of micro mirrors equal to the sum of said first, said second, said third and said fourth numbers is employed as one of the group consisting of an input MEMS device in an all-optical cross-connect and an output MEMS device in an all-optical cross-connect. 
     
     
       22. An optical switch, comprising 
       a first micro-electromechanical system (MEMS) device containing a first number of micro mirrors;  
       a second micro-electromechanical system (MEMS) device containing a second number of micro mirrors;  
       a first imaging system optically coupled to said first MEMS device so as to produce an image of said first MEMS device;  
       a second imaging system optically coupled to said second MEMS device so as to produce an image of said second MEMS device;  
       wherein said first and second imaging systems are arranged so that said image of said first MEMS device and said image of said second MEMS device form a virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers.  
     
     
       23. A method for use in an optical switch, comprising the steps of: 
       coupling (i) an image of a first micro-electromechanical system (MEMS) device containing a first number of micro mirrors and  
       (ii) at least one of the set consisting of (a) a second MEMS device containing a second number of micro mirrors and (b) an image of said second MEMS device,  
       so as to form a virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers.  
     
     
       24. The invention as defined in  claim 23  further comprising the step of forming said image of said first MEMS device such that said image of said first MEMS device is made up of light beams reflected by said micro mirrors of said first MEMS device and each of said light beams has an angle that is a function of the angle of reflection of said light beam from a respective one of said micro mirrors of said first MEMS device off of which it is reflected. 
     
     
       25. The invention as defined in  claim 23  wherein said further comprising the step of forming said image of said first MEMS device by reproducing the angle of reflection of each of said light beams from each respective one of said micro mirrors of said first MEMS device off of which it is reflected. 
     
     
       26. The invention as defined in  claim 23  further comprising the step of forming said image of said first MEMS device using a telecentric imaging system. 
     
     
       27. An optical switch, comprising 
       a first micro-electromechanical system (MEMS) device containing a first number of micro mirrors;  
       a second MEMS device containing a second number of micro mirrors;  
       a first imaging system optically coupled to said first MEMS device so as to produce an image of said first MEMS device,  
       wherein said path of said first imaging system is arranged so that said image of said first MEMS device is made up of light beams reflected by said micro mirrors of said first MEMS device, each of said light beams having an angle that is a function of the angle of reflection of said light beam from a respective one of said micro mirrors of said first MEMS device off of which it was reflected; and  
       wherein  
       (i) said image of said first MEMS device and  
       (ii) at least one of the set consisting of (a) said second MEMS device and (b) an image of said second MEMS device,  
       are arranged to form a virtual MEMS device having a number of micro mirrors equal to the sum of said first and second numbers.  
     
     
       28. An optical switch, comprising 
       first micro-electromechanical system (MEMS);  
       second MEMS means; and  
       first imaging means optically coupled to said first MEMS means at one optical end so as to produce an image of said first MEMS means at the optical end of said imaging means opposite to said optical end at which said first MEMS means is located;  
       (i) said image of said first MEMS means and  
       (ii) at least one of the set consisting of (a) said second MEMS means and (b) an image of said second MEMS means,  
       forming a virtual MEMS device having size equal to the sum of said first and second MEMS means.